1. Field of the Invention
The present invention relates to novel naphthyridine compounds, useful as antibacterial agents or as intermediates.
2. Information Disclosure Statement
Certain substituted 1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acids are known to possess antibacterial activity. Lesher and Gruett U.S. Pat. No. 3,590,036, issued June 29, 1971, describes such acids wherein the 1-position bears an optionally substituted hydrocarbon group. Illustrative of the compounds disclosed are 1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carboxylic acid (nalidixic acid) (Example 1) and 1-(2-diethylaminoethyl)-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-car boxylic acid (Example 30).
Grohe et al. U.S. Pat. No. 4,284,629, issued Aug. 18, 1981, discloses certain bicyclic 1,4-dihydro-4-pyridone-3-carboxylic acids substituted in the 1-position, inter alia, by a tertiary-amino group. Exemplary of the compounds disclosed are 1-dimethylamino-6-nitro-2-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid, methyl ester (Example 4), and 1-(4-morpholinyl)-2,7-dimethyl-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carbo xylic acid (Example 23).